Boolean Union Difficulties with Split Shank

Hello!

I am going crazy. I am working on a ring model, with a split shank. I currently have three polysurfaces, the under side of the shank, and the two upper half pieces. The three pieces meet at the two side quadrant points, they all end with the same edge curve because I used the same closed curve to sweep1 around their three curves. When I attempt to make these three pieces into one by using booean union, it fails. It is almost as if they line up too perfectly. When I move on piece out to the side a bit, I can achieve the union. What’s the deal? Does anyone know of a better way to make a simple split shank?

ALSO: I did it last week, and cannot remember how I did it. Cursing my lack of notes.

Thank you so so much for any advice or tips!

booleanunionfail.pdf (134.9 KB)

Create an XZ plane surface. Trim off the corners of red and white surfaces with it. Join to the purple surface.

Ohhh this worked perfectly!! Initially it left me with 4 naked edges, but I joined them, now I have a perfect surface. Thank you so so much, I can stop freaking out! Really brilliant solution, and so easy.

Thank you!!!